Before building a single-shot rifle, anyone should read deHaas's books. He's
the expert. His son has one or more books out, too. I haven't read them but
his dad knows his stuff, so they're probably good. DeHaas also is an
experienced critic of the common single-shot actions, and a designer of
several well-regarded ones himself. I'd stick to one of his designs or make
a straight replica of a Winchester Hi-Wall.


I have at least three of DeHaas' books. My dad got wired up on this Bill
Holmes design.

The significant question is how do you machine the passage for the block
so it's got somewhat square corners? Or is a slight radius OK? I see the
square broaches, but isn't an acutely square corner a good place for a
crack to start?

One approach would be to drill four holes at the corners of the block
passage, broach them square, then use a hole saw for gross metal
removal, followed by a 1/2" mill to square up the sides. Is there a less
manly-man way of doing it?

Before someone mentions casting, that is not an option.

For those up on DeHaas, look at the Chicopee RF. Problems: 3/16 CRS
plates welded or silver soldered to barrel area. I like the swinging
block, but I'm not sure it would do well with the 5mm. Look at the
Chicopee CF action, and the bolt locking arrangement goes from a milled
shaft (RF) to sort of a rolling block design (CF).